/Engine/Source/Runtime/Engine/Classes/GameFramework/PlayerController.h
Called on the server when the client sends a message indicating it was unable to initialize an Actor channel, most commonly because the desired Actor's archetype couldn't be serialized the default is to do nothing (Actor simply won't exist on the client), but this function gives the game code an opportunity to try to correct the problem
virtual void NotifyActorChannelFailure ( [UActorChannel](API\Runtime\Engine\Engine\UActorChannel) * ActorChan )